The white plastic bags fluttering in the treetops of the Italian Alps intrigued Fabrizio Sergio. The Italian ecologist knew the trash hung from the nests of a certain bird, the black kite.

But what still remains incredibly rare are 'white' leucistic red kites, which can be found just over the Herefordshire border at Gigrin Farm in Rhayader. There are three of the birds, with only 10 ...